Starting a diet and staying on it can be challenging, especially if you're going about it the wrong way. Crash diets and unrealistic expectations only lead to failure and weight gain. According to the National Heart, Lung and Blood Institute, weight loss reduces your risk of a variety of diseases and medical conditions, such as diabetes, high blood pressure, heart disease and certain cancers. If these weight-loss benefits aren't enough motivation to keep you committed to eating healthy, take effective steps to stay on the right track.

Change the Way You Think

Many people dislike dieting because they associate it with food deprivation and drastic restrictions. Rather than thinking of it as dieting, think of it as eating healthy. Eliminate unhealthy habits and commit to healthy habits -- eat fruit instead of cookies; eat skinless chicken instead of fatty pork; drink low-fat milk instead of full-fat milk. Dr. Donald Hensrud, M.D., a preventive medicine specialist with Mayo Clinic, suggests creating a daily deficit of 500 or 1,000 calories so you lose one or two pounds per week. According to Hensrud, slow, gradual weight loss is easier to maintain over the long run, and you don't risk losing water weight or lean muscle tissue.

Goals and Rewards

Setting realistic goals and rewarding yourself when you reach them can help you stay committed to eating healthy. Set one long-term goal and several short-term goals. A long-term goal can be to lose 15 pounds in two months; short-term goals can be to lose one or two pounds each week. At the end of each week, reward yourself for reaching your goal -- go see a movie, get a manicure or buy a CD or book. For even more motivation to succeed, Gary Latham, Ph.D., an organizational psychologist at the University of Toronto, suggests writing down your goals and displaying them on the refrigerator for all to see.

Find Support

According to research conducted at Dartmouth University and Brown Medical School, people who use the buddy system lose more weight than those who don't. Losing weight with one or more friends can help keep you on track. During moments of weakness, weight-loss buddies can keep each other from falling off the wagon. Losing weight with a friend is more fun and makes the process a social experience -- you listen to each other and motivate each other to exercise and eat healthy.

Keep a Journal

Writing down everything you eat on a daily basis can help you lose weight and motivate you to keep going. If you gain weight, a glance in your journal can help you find the culprit. By writing down what you eat, you hold yourself accountable -- most likely you won't eat that second or third cookie knowing that you have to write it in your journal. Include your exercise routine in your journal, because this also contributes to your weight loss. Even after reaching your target weight, keeping a journal can help you stay on track.